044.... WW2 German Junker Morse Code key. 1944.
The history of this key is fascinating! U Boat U-1102 was a Type V11C built at the Nordseewerke, Emden and commissioned in 1944. She was used as a training vessel until the end of hostilities in 1945, when, taken to Scotland and all useful items removed, towed out to sea in "Operation Deadlight" and sunk by naval gunfire on 21st December 1945 @ 56 deg 04'N, and 09 deg 35'W.

Stamped in red on the underside of the base is "Mar.N.I/4-20-". "Mar. N." means "Marine Nachrichtengeraete" (Navy communication equipment).

A close-up of markings showing "D.R.P. Junker".. On the right can be seen the key complete with its original equipment cable assembly. Beneath the bakelite lever are the markings "V1" and "S" followed by the numbers" 93391", followed by "Ph".
Herman / VK2IXV provides some interesting information on the logo found on the underside of the lever: "The logo on the left hand side is the Staatliche Materialpruefungsamt in Berlin-Dahlem (State Material Examination Office in Berlin-Dahlem) proof stamp, which was required on bakelite products. V1 is the manufacturer’s code. S is the bakelite material code, which in this case is a mixture of phenol, formaldehyde and a sawdust filler. The filler added strength. Other fillers were asbestos and slate dust. 93391 must be production data. A collector in Germany has a DRP Junker with same markings, but production data number is 93382. Ph is short for Phenolharz (Phenolresin = bakelite)".

Regarding the colour of a Junker key - Kriegsmarine (Navy) and Merchant Navy keys were grey, Army and NATO keys were olive green.